4. _Hamiltonian Equations of Motion._

In the Hamiltonian form of the equations of motion of a conservative

system with unvarying relations, the kinetic energy is supposed

expressed in terms of the _momenta_ p1, p2, ... and the co-ordinates

q1, q2, ..., as in Sec. 1 (19). Since the symbol [delta] now denotes a

variation extending to the co-ordinates as well as to the momenta, we

must add to the last member of Sec. 1 (21) terms of the types

dP[Tau] dP[Tau]'

------- [delta]q1 + -------- [delta]q1 + ... (1)

dPq1 dPq1

Since the variations [delta]p1, [delta]p2, ... [delta]q1, [delta]q2,

... may be taken to be independent, we infer the equations Sec. 1 (23) as

before, together with

dP[Tau] dP[Tau]' dP[Tau] dP[Tau]'

------ = - --------, ------- = - --------, ..., (2)

dPq1 dPq1 dPq2 dPq2

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